clarifying ambiguous genitalia
DESCRIPTION
The lecture explains the issue of sex development ,and the role of imaging in investigating the different situations of genital ambiguity.TRANSCRIPT
Clarifying ambiguous genitalia..Radiologist role.
Dr/Ahmed BahnassyConsultant Radiologist
RMHEmail:[email protected]
Introduction
Reproductive system development
Sexual differentiation.
ClassificationDSDs can be classified broadly into four categories on the basis of gonadal histologic features: female pseudohermaphroditism (46,XX with two ovaries)male pseudohermaphroditism (46,XY withtwo testes); true hermaphroditism (ovotesticular DSD) (both ovarian and testicular tissues); and gonadal dysgenesis :either mixed (a testis and a streak gonad) or pure (bilateral streak gonads).
Male pseudohermaphroditism
• Persistent Mullerian duct syndrome.
• Testicular unresponsiveness to HCG & LH (Leyding Cell Hypoplasia).
• 5 Alpha Reductase Deficiency.
• Androgen Insensitivity Syndrome (cAIS & pAIS).
Work-up
coordinated medical team that includes a pediatric endocrinologist, geneticist, urologist, and radiologist
to ensure timely diagnosis and proper
management.
Role of imaging
US is the primary modality for evaluation of the internal reproductive organs,
whereas genitography and voiding
cystourethrography are used for evaluation of urethral and vaginal tracts and fistulas.
MR imaging may serve as a problem-solving modality for clarifying the internal anatomy and searching for internal gonads.
Ultrasound• Renal
• Adrenal.
• Pelvis.
• Perineum.
• Both inguinal regions.
• Upper thighs !
Adrenal Imaging
partial androgen insensitivitysyndrome (Reifenstein syndrome)
Ovotesticular DSD
MGD
Fluoroscopy-Genitography
It is important to examine
all perineal orifices and insert the catheter for
a short distance into each orifice to preserve its
morphologic appearance.
A good maneuver is to
fill the balloon of an 8-F Foley catheter outside
the body and insert just the distal tip, performing
a retrograde injection.
Cloacal anomaly
Urogenital sinus
Complex urogenital sinus anomaly
Role of MRI
Ectopic gonads, testes, and noncystic
immature ovaries have intermediate signal intensity on T1-weighted MR images and high signal intensity with an intermediate-signal-intensity outer rim on T2-weighted images
Testis in MRI
Ovaries in MRI
Streak gonads are difficult to detect and can be seen as low-signal-intensity stripes on T2-weighted images .
High-signal-intensity foci in streak gonads
could represent neoplastic change .
Algorithm
Risk of Neoplasm
Because 20%–30% of children with XY PGDand 15%–20% with MGD develop a gonadalneoplasm within the 1st or 2nd decade of life,streak gonads should be removed . The presence of a well-defined part of the Y chromosome(GBY [gonadoblastoma locus on theY chromosome]) is implicated in the developmentof malignant neoplasms in dysgeneticgonads . Gonadoblastoma is the most commontumor, usually arising from dysgeneticintraabdominal gonads
Attention
The presence of an echogenic focus at
US associated with the pelvic organs or found in ectopic gonadal tissue within the inguinal canals or labioscrotal folds should be regarded with suspicion, since gonadoblastomas often calcify.
Testicular Neoplasm
Wilm’s Tumour
There is increased risk of developing
Wilms tumor, particularly when XY gonadal
dysgenesis is associated with glomerulopathy in
Drash syndrome
Breast Cancer
Risk factors for male breast cancer include conditions with increased estrogen exposure, such as advanced age, cryptorchidism, testicular injury,
Klinefelter’s syndrome, and liver dysfunction.
